Multifunctional Nanozyme Research Articles

A tripartite-enzyme via curcumin regarded as zymoexciter towards highly efficient relieving reperfusion injury

For alleviating ischemic reperfusion injury, reasonable design mimic multi-functional nanozyme can simultaneously capture ROS and inhibit inflammatory factors, which plays an important role. However, the low efficiency of natural enzyme and their ability to capture only a single species limit their effectiveness. Therefore, additional materials to capture other ROS are highly needed. These motivates us to construct a nanozyme via hybridize/coupled curcumin (CUR) with ZnCe Layered Rare-earth Hydroxide (ZnCe-LRH) to achieve highly efficient ROS scavenging efficiency and the multiple ROS capture (denoted as CUR/ZnCe-LRH). Ce element was highly dispersed on the LRH layer, and CUR further coordinated with Zn on the layer to form a stable nanozyme structure. This mimic tripartite nanozyme can not only simulate superoxide dismutase (SOD) and catalase (CAT) activity to capture •O2− and H2O2, but also arrest •OH within a short period of time, which can be regarded as the tripartite nanozyme. Density functional theory (DFT) calculations can further confirm the high efficient ROS scavenging mechanism by the CUR/ZnCe-LRH systems. In vivo results can further probe that this CUR/ZnCe-LRH can also suppress inflammation- and immune response–induced injury, thus achieving good prevention and treatment in neuroprotective therapy. The infarct area can reduce by 78% after the reperfusion therapy and the neurological deficit score can reduce from 3.50 to 0.67. This strategy provided a novel multifunctional enzyme mimetic for ischemia–reperfusion therapy and clarifies the application mechanism of neuroprotection against ischemia–reperfusion injury.

Rational Construction of a Ni/CoMoO4 Heterostructure with Strong Ni-O-Co Bonds for Improving Multifunctional Nanozyme Activity.

Due to the lack of a general descriptor to predict the activity of nanomaterials, the current exploration of nanozymes mainly depended on trial-and-error strategies, which hindered the effective design of nanozymes. Here, with the help of a large number of Ni-O-Co bonds at the interface of heterostructures, a prediction descriptor was successfully determined to reveal the double enzyme-like activity mechanisms for Ni/CoMoO4. Additionally, DFT calculations revealed that interface engineering could accelerate the catalytic kinetics of the enzyme-like activity. Ni-O-Co bonds were the main active sites for enzyme-like activity. Finally, the colorimetric signal and intelligent biosensor of Ni/CoMoO4 based on deep learning were used to detect organophosphorus and ziram sensitively. Meanwhile, the in situ FTIR results uncovered the detection mechanism: the target molecules could block Ni-O-Co active sites at the heterostructure interface leading to the signal peak decreasing. This study not only provided a well design strategy for the further development of nanozymes or other advanced catalysts, but it also designed a multifunctional intelligent biosensor platform. Furthermore, it also provided preferable ideas regarding the catalytic mechanism and detection mechanism of heterostructure nanozymes.

Construction of biomimetic nanozyme with high laccase- and catecholase-like activity for oxidation and detection of phenolic compounds

Despite the rapid development of nanozyme, it is still challenging to develop multifunctional nanozyme with high oxidase-like activity. In this work, a novel type of amorphous imidazole-Cu nanozyme (I-Cu) with high laccase- and catecholase-like activity was prepared by the water induced precipitation of Cu2+ and imidazole to mimick the N-Cu coordinated environment in their active site. I-Cu shows similar Km but 3.7-fold higher Vmax than laccase at the same mass concentration. The possible catalytic mechanism of I-Cu nanozyme, which is composed of substrate binding, substrate oxidation, oxygen binding and oxygen reduction, is proposed. In addition, it also displays high stability under various pH, temperature, long-term storage and high salinity. The oxidation efficiency of I-Cu nanozyme for environmental phenolic pollutants (2,4-dichlorophenol) is 91.8% at 10 h, which is higher than that of laccase (68.8% at 10 h). Furthermore, the colorimetric and smart phone detection of dopamine by I-Cu nanozyme is developed with the detection limit of 0.412 μM. Therefore, we expect this amorphous nanozyme is promising in the various application of bioremediation and biosensor.

Preparation of amorphous MOF based biomimetic nanozyme with high laccase- and catecholase-like activity for the degradation and detection of phenolic compounds

In spite of the rapid development of nanozyme, it is still challenging to develop multifunctional nanozyme with high oxidase-like activity. In this work, a novel type of amorphous MOF based nanozyme (CA-Cu) with both laccase- and catecholase-like activity was prepared by the facile solvothermal reaction of cyanuric acid and Cu2+ to mimick the N-Cu coordinated environment between the imidazole and Cu2+ in their active site. Due to the excellent activity, substrate universality, recyclability and stability of CA-Cu nanozyme, it shows broad application prospects in degradation and detection of phenolic compounds. Besides, the structure–activity relationship between N-Cu coordinated environment and laccase/catecholase-like activity has been further proved.

"Three-in-one" nanocomposites as multifunctional nanozymes for ultrasensitive ratiometric fluorescence detection of alkaline phosphatase.

Nanozymes, as a unique class of nanomaterials with enzyme-like properties, have attracted significant interest due to their potential applications in many significant fields. Great endeavours have been made to improve the catalytic activities of nanozymes; however, it is still a challenging issue to develop nanozymes that can functionally mimic multiplex enzymes with broader application prospects. Here, we develop a simple hydrothermal method to construct "three-in-one" nanocomposites as multifunctional nanozymes for the ultrasensitive ratiometric fluorescence detection of alkaline phosphatase (ALP). The prepared flower-like Fe3O4 nanocomposites (Fef NCs) are composed of ternary components, in which hierarchical MnO2 nanosheets (NSs) are assembled on Fe3O4 nanoparticles (NPs), followed by the decoration of CeO2 NPs. Fef NCs present tetra-enzyme-like activities, i.e., oxidase-, peroxidase-, catalase-, and superoxide dismutase-like activity. More importantly, Fef NCs can effectively catalyze the oxidation of phenolic compounds (i.e., 3,5-DTBC and dopamine) to produce the corresponding o-quinones, demonstrating specific catechol oxidase-like activity. Based on the excellent catalytic oxidation and fluorescence quenching abilities of Fef NCs, we established a ratiometric fluorescence strategy using two fluorogenic substrates for label-free, ultrasensitive, and selective detection of ALP. The fluorescence bioassay exhibits a linear relationship between the fluorescence ratio and the ALP concentration ranging from 0.2 to 1.0 mU mL-1, with a detection limit down to be 0.19 mU mL-1. Furthermore, this bioassay can detect ALP in mixture and human serum samples, presenting good selectivity as well as real-world applicability. This work not only provides a novel approach for the preparation of a multiple-enzyme-like nanozyme but also offers an advanced ratiometric fluorescence sensing platform for ultrasensitive bioanalysis.

Biomimetic multifunctional nanozymes enhanced radiosensitization for breast cancer via an X-ray triggered cascade reaction.

Radiotherapy has been widely applied for breast cancer treatment in the clinic, while improving the radiation sensitivity of tumors and protecting normal tissues from radiation damage has drawn considerable attention. In this study, we reported a biomimetic multifunctional nanozyme (BSA@CeO/Fe2+), which can be used as a radiosensitizer for breast cancer treatment. It was demonstrated that BSA@CeO/Fe2+ presented a pH dependent multiple enzyme like activity that enhances the hydroxyl radical level by cascade catalytic reactions in a tumor microenvironment to obtain a desirable tumor-suppression rate (83.07%). Moreover, BSA@CeO/Fe2+ was also proved to reduce reactive oxygen species levels in normal cells. Additionally, BSA@CeO/Fe2+ nanozymes showed no obvious toxicity by routine blood examination and blood biochemistry assays. Therefore, this work provided a promising strategy for nanocatalytic tumor therapy by rationally designing biomimetic nanozymes with multienzymatic activities for achieving high radiotherapy efficacy and excellent biosafety simultaneously.

Multifunctional Nanozyme Hydrogel with Mucosal Healing Activity for Single-Dose Ulcerative Colitis Therapy.

Nanozymes are nanomaterials with enzyme-like activities, which have been developed for inflammatory disease therapy by reactive oxygen species (ROS) scavenging. The application of nanozymes in ulcerative colitis (UC) treatment not only inherits the merits of small molecular antioxidants (e.g., 5-aminosalicylic acid) to scavenge ROS but also achieves catalytic recycle instead of stoichiometric consumption. However, current therapies usually ignore the repair of mucosa, the first line of defense, whose damage increases the risk of infections. Herein, a multifunctional nanozyme hydrogel is designed and verified both as an ROS scavenger and a mucosal healing enhancer for UC therapy. The chitosan-coated CeO2 nanozyme (CCNZ) not only possesses excellent ROS-scavenging ability but also exhibits satisfactory antibacterial capacity. After gelation with alginate, the optimized CCNZ1:Alg1.5 nanozyme hydrogel exhibits multiple functions, including inflamed site targeting, supporting cell growth, ROS scavenging, and antibacterial activity, which alleviates UC better than a clinical medication 5-aminosalicylic acid by even a single-dose treatment. This study reveals that a nanozyme providing mucosal healing is promising for UC therapy with excellent potential for clinical application and enriches the nanozyme research of treatment for diseases.

A multifunctional nanozyme-based enhanced system for tert-butyl hydroquinone assay by surface-enhanced Raman scattering.

An Au-based nanozyme composite (AuNPs/Cu,I) was constructed by using Cu,I-doped carbon dots (Cu,I-CDs) as the reducing agent as well as the nanozyme. Notably, AuNPs/Cu,I nanozyme not only possessed the intrinsic activity of mimicking enzymes of superoxide dismutase, peroxidase, and catalase at different conditions but was also employed as surface-enhanced Raman spectroscopy (SERS) enhancer. The combination of Cu,I-CDs and AuNPs promoted the electron transferability, leading to increased peroxidase-like activity and superoxide-like activity. Compared to the individual Cu,I-CDs and AuNPs nanozyme, the AuNPs/Cu,I composite demonstrated promising peroxidase-like activity by transferring electrons instead of generating OH. Interestingly, the multienzyme-like activity of AuNPs/Cu,I nanozyme could be finely tuned by changing the composition of Cu0/Cu+ and Au. Thetert-butyl hydroquinone (TBHQ) as the substrate could be catalyzed with AuNPs/Cu,I nanozyme to produce red substances, resulting in a significant Raman enhancement effect at the same time, showing good linear range from 0.11 to 10mg L-1. Overall, the current investigation provides a flexible and controllable way to design multifunctional nanozymes along with the Raman enhancement strategy based on the catalysis of nanozyme.

A pH-Responsive Persistent Luminescence Nanozyme for Selective Imaging and Killing of Helicobacter pylori and Common Resistant Bacteria.

Helicobacter pylori (H. pylori) infection is implicated in the etiology of many diseases. H. pylori eradication by antibiotic therapy is limited by the extreme acidic environment in the stomach, the undesired side effect of intestinal commensal bacteria, and the development of drug resistance. Here, we report a pH-responsive persistent luminescence (PL) nanozyme (MSPLNP-Au-CB) for in vivo imaging and inactivation of H. pylori. This PL nanozyme is composed of mesoporous silica (MS)-coated persistent luminescence nanoparticles (MSPLNP), Au nanoparticles (AuNP), and chitosan-benzeneboronic acid (CB), taking advantage of the long PL of PLNP to realize autofluorescence-free imaging, the pH-activated oxidase- and peroxidase-like nanozyme activity of AuNP, and the bacterial binding capacity of CB. The MSPLNP-Au-CB nanozyme can resist the corrosion of gastric acid and exhibit pH-activated dual nanozyme activity to catalyze bactericidal reactive oxygen species generation. This multifunctional nanozyme enables targeted imaging and activated deactivation of H. pylori under extreme gastric acid conditions as well as methicillin-resistant Staphylococcus aureus in common slightly acidic environments, while it has no side effects on the commensal bacteria and normal cells in normal physiological environments. This work provides a promising PL nanozyme platform for bioimaging and therapy of bacterial infection under harsh conditions.

Construction multifunctional nanozyme for synergistic catalytic therapy and phototherapy based on controllable performance

Advances in nanozyme involve an efficient catalytic process, which has demonstrated great potential in tumor therapy. The key to improving catalytic therapy is to solve the limitation of the tumor microenvironment on Fenton reaction. In this work, Prussian blue nanoparticles doped with different rare earth ions (Yb3+, Gd3+, Tm3+) were screened to perform synergistic of photothermalandcatalytictumortherapy. The optimized catalytic performance can be further enhanced through photothermal effect to maximize the Fenton reaction to solve the limitation of the tumor microenvironment. Yb-PB, with the optimal photothermal and catalytic performance, was screened out. In order to avoid the scavenging effect of glutathione (GSH) on ·OH in tumor cells and the reaction with a bit H2O2 in normal cells, GSH targeted polydopamine (PDA) was wrapped on the surface of Yb-PB to obtain Yb-PB@PDA. It was found that enough hydroxyl radicals (·OH) can be generated even if at high GSH concentration and the NIR irradiation can help produce more ·OH. Cell fluorescence imaging (FOI) and in vivo magnetic resonance imaging (MRI) experiments showed the potential application in FOI/MRI dual-mode imaging guided therapy. In vivo anti-tumor experiments showed that Yb-PB@PDA has a satisfactory anti-cancer effect through the combined effect of catalytic/photothermal therapy. Thus, a multifunctional nanozyme for tumor therapy is constructed.

The Application of Nanozymes in the Diagnosis and Treatment of TUMOR: A Review

Nanozyme is a kind of nanomaterial with simulated enzyme activity. Due to its high catalytic efficiency, better stability and modifiability, the role of nanozymes in medicine, especially in the diagnosis and treatment of tumors, is receiving more and more attention. Nanozymes usually contain metals and are often used in combination with drugs or antigens/antibodies to become multifunctional materials for the diagnosis and treatment of tumors. At present, the detailed synthesis, classification and function of nanozymes need to be supplemented. In our review, we introduce the research status, synthesis and classification of nanozymes roundly. Then we summarized and introduced some characteristic nanozymes according to their functions, mainly including tumor diagnosis, tumor therapy, tumor surgical adjuvant therapy and multifunctional complexes. We believe that many breakthroughs have been made in the research of nanozymes, and more and more multifunctional nanozymes have been studied. However, there are still some shortcomings in the current research on nanozymes such as the lack of solutions to some of the insufficient properties of nanoparticles, like spontaneous aggregation, nonspecific phagocytosis, etc. At the same time, the catalytic reaction is relatively simple, which limits the further application of nanozyme. In our review, we made our own comments and prospects on the diagnostic, therapeutic and application of nanozymes. In the future, nanozymes will play an increasingly important role in the diagnosis and treatment of tumors due to their potential modifiability and versatility as well as their increasingly perfect physicochemical properties.

Photothermal nanozyme-ignited Fenton reaction-independent ferroptosis for breast cancer therapy

Ferroptosis is a type of programmed cell death caused by the iron-dependent lipid hydroperoxide pathway and has attracted significant interest. However, Fenton reaction-dependent ferroptosis has shown unsatisfactory therapeutic effects in tumor therapy, mainly due to inadequate reaction conditions in the tumor microenvironment. Here, we report a new strategy for Fenton-independent pathway by employing photothermal nanozyme to overcome limitations of the low efficiency of Fenton reaction. Specifically, we used iron redox pair (Fe2+/Fe3+)-containing hollow mesoporous Prussian blue (HMPB) nanocubes as the iron sources to fabricate iron-loaded liposome (HMPB@Lip). HMPB@Lip not only exerts the photothermal therapy, but also functions as nanozyme catalyzing lipid peroxidation for ferroptosis therapy. Importantly, Fenton reaction-independent ferroptosis triggered by photothermal nanozyme achieved effective tumor ablation. Therefore, HMPB@Lip can be used as a potential multifunctional nanozyme for effective Fenton reaction-independent ferroptosis therapy.

Black phosphorus quantum dots as multifunctional nanozymes for tumor photothermal/catalytic synergistic therapy

Black phosphorus quantum dots as multifunctional nanozymes for tumor photothermal/catalytic synergistic therapy

Proton-Regulated Catalytic Activity of Nanozymes for Dual-Modal Bioassay of Urease Activity.

Benefiting from the merits of high stability and superior activity, nanozymes are recognized as promising alternatives to natural enzymes. Despite the great leaps in the field of therapy and colorimetric sensing, the development of highly sensitive nanozyme-involved photoelectrochemical (PEC) biosensors is still in its infancy. Specifically, the investigation of multifunctional nanozymes facilitating different catalytic reactions remains largely unexplored due to the difficulty in synergistically amplifying the PEC signals. In this work, mesoporous trimetallic AuPtPd nanospheres were synthesized with both efficient oxidase and peroxidase-like activities, which can synergistically catalyze the oxidation of 4-chloro-1-naphthol to produce benzo-4-chlorohexadienone precipitation on the surface of photoactive materials, and thus lead to the decreased photocurrent as well as increased charge-transfer resistance. Inspired by the proton-dependent catalytic activity of nanozymes, a self-regulated dual-modal PEC and electrochemical bioassay of urease activity was innovatively established by in situ regulating the activity of AuPtPd nanozymes through urease-mediated proton-consuming enzymatic reactions, which can remarkably improve the accuracy of the assay. Meanwhile, the determination of urease activity in spiked human saliva samples was successfully realized, indicating the reliability of the biosensor and its application prospects in clinical diagnosis.

Tumor Microenvironment-Modulated Nanozymes for NIR-II-Triggered Hyperthermia-Enhanced Photo-Nanocatalytic Therapy via Disrupting ROS Homeostasis.

PurposeReactive oxygen species (ROS) are a group of signaling biomolecules that play important roles in the cell cycle. When intracellular ROS homeostasis is disrupted, it can induce cellular necrosis and apoptosis. It is desirable to effectively cascade-amplifying ROS generation and weaken antioxidant defense for disrupting ROS homeostasis in tumor microenvironment (TME), which has been recognized as a novel and ideal antitumor strategy. Multifunctional nanozymes are highly promising agents for ROS-mediated therapy.MethodsThis study constructed a novel theranostic nanoagent based on PEG@Cu2-xS@Ce6 nanozymes (PCCNs) through a facile one-step hydrothermal method. We systematically investigated the photodynamic therapy (PDT)/photothermal therapy (PTT) properties, catalytic therapy (CTT) and glutathione (GSH) depletion activities of PCCNs, antitumor efficacy induced by PCCNs in vitro and in vivo.ResultsPCCNs generate singlet oxygen (1O2) with laser (660 nm) irradiation and use catalytic reactions to produce hydroxyl radical (•OH). Moreover, PCCNs show the high photothermal performance under NIR II 1064-nm laser irradiation, which can enhance CTT/PDT efficiencies to increase ROS generation. The properties of O2 evolution and GSH consumption of PCCNs achieve hypoxia-relieved PDT and destroy cellular antioxidant defense system respectively. The excellent antitumor efficacy in 4T1 tumor-bearing mice of PCCNs is achieved through disrupting ROS homeostasis-involved therapy under the guidance of photothermal/photoacoustic imaging.ConclusionOur study provides a proof of concept of “all-in-one” nanozymes to eliminate tumors via disrupting ROS homeostasis.

Hemin Covalently Functionalized Carbon Nanobranch with Enzyme‐Like and Photocatalytic Activities for Synergistic Dye Degradation and Antibacterial Therapy

AbstractThe development of artificial enzymes with excellent enzyme‐like activities and unique features is highly desirable for their practical applications. Herein, a one‐pot facile method to synthesize hemin covalently functionalized carbon nanobranch (CN‐hemin) via direct pyrolysis of citric acid and covalent coupling of hemin to the formed carbon skeleton, is reported. This strategy is reasonably straightforward, cheap, and environmentally friendly, without any extraneous oxidant, reductant, and harmful additives during the preparation process. Furthermore, the obtained dendritic hybrids possess good water‐solubility, intrinsic peroxidase‐like activity, and satisfactory photocatalytic performance in visible light. These extraordinary properties are mainly due to the structure of CN‐hemin which contains iron porphyrin, aromatic carbon, and citric acid residues. Most importantly, under visible light irradiation, the as‐prepared hemin‐incorporated nanohybrid can act as robust agents for synergistic dye degradation and antibacterial therapy toward Staphylococcus aureus and methicillin‐resistant S. aureus. It is expected that this study can shed valuable light on developing advanced multifunctional nanozymes with combined favorable properties for highly efficient elimination of environmental pollutants and antibacterial treatment.

Multifaceted Therapy of Nanocatalysts in Neurological Diseases.

With the development of enzymes immobilization technology and the discover of nanozymes, catalytic therapy exhibited tremendous potential for neurological diseases therapy. In especial, since the discovery of Fe₃O₄ nanoparticles possessing intrinsic peroxidase-like activity, various nanozymes have been developed and recently started to explore for neurological diseases therapy, such as Alzheimer's disease, Parkinson's disease and stroke. By combining the catalytic activities with other properties (such as optical, thermal, electrical, and magnetic properties) of nanomaterials, the multifunctional nanozymes would not only alleviate oxidative and nitrosative stress on the basis of multienzymes-mimicking activity, but also exert positive effects on immunization, inflammation, autophagy, protein aggregation, which provides the foundation for multifaceted treatments. This review will summarize various types of nanocatalysts and further provides a valuable discussion on multifaceted treatment by nanozymes for neurological diseases, which is anticipated to provide an easily accessible guide to the key opportunities and current challenges of the nanozymes-mediated treatments for neurological diseases.

Multifunctional nanozyme for multimodal imaging-guided enhanced sonodynamic therapy by regulating the tumor microenvironment.

Sonodynamic therapy (SDT) is a highly promising approach for cancer therapy, but its efficacy is severely hampered by the low specificity of sonosensitizers and the unfavorable characteristics of the tumor microenvironment (TME), such as hypoxia and glutathione (GSH) overexpression. To solve these problems, in this work, we encapsulated IR780 and MnO2 in PLGA and linked Angiopep-2 (Ang) to synthesize a multifunctional nanozyme (Ang-IR780-MnO2-PLGA, AIMP) to enhance SDT. With Ang functionalization to facilitate blood-brain barrier (BBB) penetration and glioma targeting, and through the function of IR780, these nanoparticles (NPs) showed improved targeting of cancer cells, especially mitochondria, and spread deep into tumor centers. Upon low-intensity focused ultrasound (LIFU) irradiation, reactive oxygen species (ROS) were produced and induced tumor cell apoptosis. Combined with the specific mitochondria-targeting ability of IR780, the sonodynamic effects were amplified because mitochondria are sensitive to ROS. In addition, MnO2 exhibited enzyme-like activity, reacting with the high levels of hydrogen protons (H+), H2O2 and GSH in the TME to continuously produce oxygen and consume GSH, which further enhanced the effect of SDT. Moreover, Mn2+ can be released in response to TME stimulation and used as a magnetic resonance (MR) contrast agent. In addition, IR780 has photoacoustic (PA)/fluorescence (FL) imaging capabilities. Our results demonstrated that AIMP NPs subjected to LIFU triggering maximally enhanced the therapeutic effect of SDT by multiple mechanisms, including multiple targeting, deep penetration, oxygen supply in situ and GSH depletion, thereby significantly inhibiting tumor growth and distal metastasis without systemic toxicity. In summary, this multifunctional nanozyme provides a promising strategy for cancer diagnosis and treatment under the intelligent guidance of multimodal imaging (PA/FL/MR) and may be a safe clinical translational method.

MOF-derived Co3O4@Co-Fe oxide double-shelled nanocages as multi-functional specific peroxidase-like nanozyme catalysts for chemo/biosensing and dye degradation

Nanozymes are attractive alternatives to natural enzymes due to their high stability and low cost. However, it is still a great challenge to acquire highly active, specific, and multi-functional nanozyme catalysts for chemo/biosensing and peroxymonosulfate (PMS) activation to degrade toxic dye pollutants. Metal-organic frameworks are attractive templates to construct multi-functional catalysts. Herein, Co3O4@Co-Fe oxide double-shelled nanocages (DSNCs) were prepared via anion-exchange combined with low-temperature pyrolysis by using ZIF-67 as a starting template. They maximized the advantages of a hollow nanostructure, acting as both nanoreactor and substrate channel, to mimic enzymes. This enables high peroxidase-like activity and very weak oxidase-like activity. The Km value of Co3O4@Co-Fe oxide DSNCs for H2O2 was 1.38 and 3.33-fold lower than those of single-shelled Co-Fe oxide and Co3O4 nanozymes, respectively. The high peroxidase-like activity of Co3O4@Co-Fe oxide DSNCs enabled H2O2 linear detection over the range 0.02 to 600 μM, with a detection limit of 20 nM. When coupled with the acetylcholinesterase/acetylthiocholine cascade enzymatic reaction, we proposed an ultra-sensitive colorimetric platform for acetylcholinesterase activity screening in the linear range over 8 × 10−4–1 mU mL−1, with a detection limit of 2 × 10−4 mU mL−1. The Co3O4@Co-Fe oxide DSNCs can active PMS to degrade 99.1% of acid fuchsin within 20 min, along with good reusability over ten-cycle run. The kinetics of 15 mg L−1 acid fuchsin degradation was 0.176 min−1 at 25 °C with 300 mg L−1 PMS and 150 mg L−1 DSNCs. This work details the attractive applications of DSNCs for chemo/biosensing and dye degradation.

<p>Cyclodextrin-Modified CeO<sub>2</sub> Nanoparticles as a Multifunctional Nanozyme for Combinational Therapy of Psoriasis</p>

PurposeReactive oxygen species (ROS)-induced oxidative stress plays a key role in the pathogenesis and progression of psoriasis by causing inflammation. Antioxidative strategies eradicating ROS may serve as effective and easy treatment options for psoriasis, while nanozymes with intrinsic antioxidant enzyme-like activity have not been explored for psoriasis treatment. The aim of this study is to fabricate β-cyclodextrins (β-CDs)-modified ceria nanoparticles (β-CDs/CeO2 NPs) with drug-loaded and multimimic-enzyme activities for combinational psoriasis therapy.MethodsThe β-CDs/CeO2 NPs were synthesized by a hydrothermal method using unmodified β-CDs as a protecting agent. The structure, size and morphology were analyzed by dynamic light scattering, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. Considering the superoxide dismutase (SOD)- and catalase-mimetic activities, the in vitro antioxidant activity of the β-CDs/CeO2 NPs was investigated. After dithranol (DIT) was loaded, the drug-loading capacity and release profile were determined by UV-visible light spectrophotometer and high-performance liquid chromatography. The anti-psoriatic efficacy was studied in the imiquimod (IMQ)-induced mouse model on the basis of morphological evaluation, psoriasis area and severity index calculation (PASI), and inflammatory cytokine expression.ResultsThe average particle size of the blank β-CDs/CeO2 NPs was 60.89±0.32 nm with a polydispersity index (PDI) of 0.12, whereas that of the DIT-loaded NPs was 79.38±1.06 nm with a PDI of 0.27. TEM results showed the as-prepared NPs formed a uniform quasi-spherical shape with low polydispersity. XPS indicates synthesized NPs have a mixed Ce3+/Ce4+ valence state. FTIR spectroscopy confirmed the presence of β-CDs and DIT in the NPs. Inhibition of superoxide anion rate by NPs could be reached to 79.4% in the presence of 200 µg/mL, and elimination of H2O2 efficiency reached about 50% in the presence of 40 µg/mL, demonstrating excellent superoxide dismutase- and catalase-mimicking activities, thereby providing remarkable cryoprotection against ROS-mediated damage. Furthermore, β-CDs on the surface endowed the NPs with drug-loading function via host–guest interactions. The entrapment efficiency and drug loading of DIT are 94.7% and 3.48%, respectively. The in vitro drug release curves revealed a suitable release capability of DIT@β-CDs/CeO2 NPs under physiological conditions. In IMQ-induced psoriatic model, the DIT@β-CDs/CeO2 NPs exhibited excellent therapeutic effect.ConclusionThis study may pave the way for the application of nanozyme β-CDs/CeO2 NPs as a powerful tool for psoriasis therapy.